Layers of the Earth online activity for 6th - Free Printable

Let’s go step by step to solve this worksheet.

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Part A: Label the layers of the Earth

We are given four labels:
- Crust
- Inner Core
- Mantle
- Outer Core

And we need to match them to the colored boxes pointing to each layer in the diagram.

Looking at the Earth from outside to inside:

1. The outermost thin blue layer → that’s the Crust (it’s the surface we live on).
2. The next thick brownish layer under the crust → that’s the Mantle.
3. Then the orange layer → that’s the Outer Core.
4. The very center yellow circle → that’s the Inner Core.

So, matching the boxes from top to bottom in the diagram:

- Top blue box → Crust
- Second brown box → Mantle
- Third orange box → Outer Core
- Bottom yellow box → Inner Core

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Part B: Read each description and write the correct layer

Let’s take each one:

1. It is the thickest layer → That’s the Mantle. It makes up most of Earth’s volume.

2. It is solid due to the pressure of the other layers above it → Even though it’s super hot, the Inner Core is solid because of extreme pressure.

3. It is the thinnest layer → That’s the Crust. It’s like the skin of an apple compared to the whole fruit.

4. The upper part of this layer is liquid rock → That’s the Mantle. The upper mantle has a soft, partially melted layer called the asthenosphere — where magma comes from.

5. It is the layer above the inner core → That’s the Outer Core. It surrounds the inner core.

6. It is made up of rock and dirt and also has water → That’s the Crust. We live here — soil, rocks, oceans, all on the crust.

7. It is made of iron and nickel → Both the Inner Core and Outer Core are made of iron and nickel. But since the question says “it” (singular), and both cores fit, but typically when people say “made of iron and nickel” without specifying state, they mean the core in general. However, looking at context, since #2 already used “Inner Core” for being solid under pressure, and #5 used “Outer Core” as above inner core, then #7 likely refers to both, but since we must pick one per line, and the outer core is liquid iron/nickel, and inner is solid — actually, BOTH are made of iron and nickel. But let’s check standard curriculum: usually, this clue points to the core — but since we have two separate core layers, and the question doesn’t specify, we should look again.

Wait — re-read: “It is made of iron and nickel” — this applies to both Inner and Outer Core. But in many textbooks, they say the *entire core* is iron and nickel. Since the worksheet separates them, and we’ve already assigned Inner and Outer elsewhere, perhaps this is meant for Outer Core? No — actually, let’s think: the Inner Core is solid iron-nickel, Outer Core is liquid iron-nickel. So both qualify. But maybe the question expects “Core” — but we don’t have “Core” as an option — only Inner and Outer.

Actually, looking back at Part A, we labeled both separately. In Part B, question 7 probably refers to both, but since we can only write one answer per blank, and the most common association is that the *core* (as a whole) is iron and nickel — but since we must choose between Inner or Outer... Hmm.

Wait — let’s see what’s left. Let’s list our answers so far:

1. Mantle
2. Inner Core
3. Crust
4. Mantle
5. Outer Core
6. Crust
7. ??? — Only Inner Core and Outer Core are left unassigned? Wait no — we’ve used:

Used:
- Mantle (Q1, Q4)
- Inner Core (Q2)
- Crust (Q3, Q6)
- Outer Core (Q5)

So for Q7, we haven’t used either core twice? Actually, we can reuse if needed — but let’s think scientifically.

Standard fact: The core (both inner and outer) is made of iron and nickel. But since the worksheet splits them, and Q2 says “solid due to pressure” → Inner Core, Q5 says “above inner core” → Outer Core, then Q7 “made of iron and nickel” — this could apply to either, but often in elementary science, they say the *inner core* is solid iron-nickel, and *outer core* is liquid iron-nickel. So both are correct, but perhaps the expected answer is Inner Core? Or maybe Outer Core?

Wait — let’s check online or standard knowledge: Actually, many sources say “the core is made of iron and nickel” — referring to both. But since we have to pick one, and Q2 already took Inner Core for being solid under pressure, and Q5 took Outer Core for being above inner core, then Q7 might be intended for Outer Core? No — that doesn’t make sense.

Perhaps I made a mistake earlier.

Let me reassign carefully.

Actually, let’s look at question 4: “The upper part of this layer is liquid rock” — that’s definitely the Mantle (asthenosphere).

Question 7: “It is made of iron and nickel” — this is true for both Inner and Outer Core. But in many multiple-choice contexts, they accept “Core” — but here we have to choose from the four.

Perhaps the worksheet allows repeating answers? Looking at the blanks, there’s no instruction against it.

But let’s see: if we assign Q7 to Inner Core, then we’re using Inner Core twice (Q2 and Q7). Is that okay? Yes, because different properties.

Similarly, Outer Core could be used for Q5 and Q7.

But which one is more accurate? Actually, both are equally accurate. However, in some curricula, they emphasize that the *inner core* is solid iron-nickel, and *outer core* is liquid iron-nickel — so both are made of those materials.

But let’s think about the wording: “It is made of iron and nickel” — no mention of state. So either is fine. But to avoid conflict, let’s see which one hasn’t been used yet.

In my initial assignment:

Q2: Inner Core (for solid under pressure)
Q5: Outer Core (for above inner core)
Q7: ?

If I put Inner Core for Q7, that’s fine. If I put Outer Core, also fine.

But wait — there’s another way: perhaps Q7 is meant for the Outer Core, because sometimes they say the outer core is where the magnetic field is generated due to moving iron-nickel liquid.

But I think it’s safer to say that both are correct, but since the worksheet likely expects one answer, and given that the inner core is often highlighted as "solid iron-nickel", and outer as "liquid iron-nickel", and the question doesn't specify state, I'll go with Inner Core for Q7, as it's commonly associated.

Wait — let's double-check with standard facts:

- Crust: rock, soil, water — Q6
- Mantle: thickest, upper part has molten rock — Q1 and Q4
- Outer Core: liquid, above inner core — Q5
- Inner Core: solid due to pressure, made of iron-nickel — Q2 and Q7

Yes, that works. So Q7 can be Inner Core.

But hold on — Q2 says "solid due to pressure" — that's Inner Core. Q7 says "made of iron and nickel" — also Inner Core. That's acceptable.

Alternatively, some might argue Outer Core is also made of iron and nickel, so why not assign Q7 to Outer Core? But then Q5 is already Outer Core.

Actually, let's count how many times each layer is used:

If:
Q1: Mantle
Q2: Inner Core
Q3: Crust
Q4: Mantle
Q5: Outer Core
Q6: Crust
Q7: Inner Core

Then:
- Crust: 2 times (Q3, Q6)
- Mantle: 2 times (Q1, Q4)
- Outer Core: 1 time (Q5)
- Inner Core: 2 times (Q2, Q7)

That seems balanced.

If I put Q7 as Outer Core, then:
- Outer Core: 2 times (Q5, Q7)
- Inner Core: 1 time (Q2)

Also balanced.

But scientifically, both cores are made of iron and nickel. However, in many educational resources, when they say "made of iron and nickel" without qualification, they might be referring to the core as a whole, but since we have to choose, and the inner core is often emphasized as the "iron-nickel ball", I'll stick with Inner Core for Q7.

Wait — let's think differently. Look at question 2: "It is solid due to the pressure..." — that's uniquely Inner Core.

Question 5: "layer above the inner core" — uniquely Outer Core.

Question 7: "made of iron and nickel" — this is true for both, but perhaps the worksheet intends for us to use Outer Core here, because sometimes they say the outer core is responsible for Earth's magnetic field due to its liquid iron-nickel.

I recall that in some worksheets, "made of iron and nickel" is paired with the core in general, but since we have two, and to distribute, let's see the answer key logic.

Actually, upon second thought, let's search my knowledge: In standard K-8 science, the following is typical:

- Crust: thin, rocky, has water
- Mantle: thick, semi-solid, upper part flows
- Outer Core: liquid, iron and nickel
- Inner Core: solid, iron and nickel

So for "made of iron and nickel", it could be either, but often they specify "liquid iron and nickel" for outer, "solid" for inner.

Since the question doesn't specify, and to avoid duplication, perhaps the intended answer for Q7 is Outer Core, because Q2 already covers Inner Core's solidity.

But I think it's better to be accurate: both are made of iron and nickel. However, since the worksheet has only one blank, and we must choose, I will go with Inner Core for Q7, as it is the densest and most associated with pure iron-nickel.

No — let's change strategy. Let's look at the descriptions again.

Another approach: perhaps for Q7, since it doesn't specify state, and both are correct, but in the context of the worksheet, after assigning others, the remaining unique property might point to Outer Core.

I found a better way: let's list the layers and their key features:

- Crust: thinnest, has rock/dirt/water
- Mantle: thickest, upper part has liquid rock (magma)
- Outer Core: liquid, above inner core, made of iron/nickel
- Inner Core: solid due to pressure, made of iron/nickel

So for Q7, "made of iron and nickel" — this is a property of both, but if I have to choose one, and since Q2 is already "solid due to pressure" for Inner Core, then Q7 could be for Outer Core to balance.

But I think it's arbitrary. However, to resolve this, let's consider that in some curricula, they say the "core" is iron and nickel, and since the outer core is larger in volume than the inner core, perhaps Outer Core is more representative.

I recall that the outer core is about 2200 km thick, inner core is 1220 km radius, so outer core has more volume, but still.

Perhaps the worksheet expects "Core" but since it's split, and to match common answers, I'll go with Outer Core for Q7, because sometimes they associate the magnetic field generation with the outer core's iron-nickel flow.

But I'm overcomplicating.

Let me check a reliable source in my mind: National Geographic says "The core is made of two layers: the outer core, which borders the mantle, and the inner core. The outer core is about 1,400 miles thick, and consists of mostly iron and nickel." Similarly for inner core.

So both are correct.

For the sake of this exercise, since the student needs a clear answer, and to avoid leaving it ambiguous, I will assign Q7 to Inner Core, as it is often the focus for "iron-nickel sphere".

But let's see the final decision.

Upon reflection, I think the safest is to assign based on uniqueness:

- Q2: Inner Core (only one that is solid due to pressure)
- Q5: Outer Core (only one above inner core)
- Q7: since both are made of iron and nickel, but the description doesn't distinguish, and to use each layer at least once, but we've already used all.

Actually, all layers are used at least once by Q6.

Perhaps the intended answer for Q7 is Outer Core, because in some worksheets, they say "the outer core is made of liquid iron and nickel", and "inner core is solid iron and nickel", so for "made of iron and nickel" without state, it might be outer.

I found a better way: let's look at the number of questions. There are 7 questions, and 4 layers, so some layers will be used multiple times.

Commonly in such worksheets:

- Crust: thinnest, has water/rock
- Mantle: thickest, has magma
- Outer Core: liquid, above inner core
- Inner Core: solid, iron-nickel

So for Q7, "made of iron and nickel" — this is often paired with Inner Core in simple terms.

I think I'll go with Inner Core for Q7.

Final decision for Part B:

1. Mantle
2. Inner Core
3. Crust
4. Mantle
5. Outer Core
6. Crust
7. Inner Core

Yes.

Now, to confirm:

- Q1: thickest -> Mantle ✓
- Q2: solid due to pressure -> Inner Core ✓
- Q3: thinnest -> Crust ✓
- Q4: upper part liquid rock -> Mantle (asthenosphere) ✓
- Q5: above inner core -> Outer Core ✓
- Q6: rock, dirt, water -> Crust ✓
- Q7: made of iron and nickel -> Inner Core (also Outer Core, but we'll use Inner Core here) ✓

Some might argue for Outer Core for Q7, but I think Inner Core is acceptable.

To be precise, let's note that both cores are made of iron and nickel, but since the question likely expects one answer, and Inner Core is frequently cited as the "iron-nickel core", I'll keep it.

So, compiling the answers.

Final Answer:

Part A:
- Top blue box: Crust
- Second brown box: Mantle
- Third orange box: Outer Core
- Bottom yellow box: Inner Core

Part B:
1. Mantle
2. Inner Core
3. Crust
4. Mantle
5. Outer Core
6. Crust
7. Inner Core